中间渠道次生波发育长度数值模拟研究

分散梯级船闸充、泄水会引起船闸中间渠道内水体振荡波动，严重时会增加船舶操控难度，甚至引发安全事故。国内外专家学者针对中间渠道非恒定波流特性的研究主要集中于长波的波动特性，对次生波的关注甚少。针对三峡水运新通道分散梯级船闸布置方案，建立了基于船闸输水基本方程和Boussinesq方程的船闸-中间渠道耦合数学模型，研究船闸充、泄水条件下中间渠道次生波发育长度的分布特性及其对相关水力参数的响应规律。结果表明:上级船闸泄水条件下，次生波发育长度与单宽峰值流量有关；而下级船闸充水时，次生波的发育长度取决于单宽峰值流量和船闸运行水头。基于数值计算结果，给出了船闸不同运行方式下次生波发育长度的预测方法，可为分散梯级船闸的设计和运行调度提供理论指导和技术支撑。

A numerical study on the development length of secondary waves in an intermediate navigation channel

The intermediate channel between two decentralized cascade locks is an impounded navigation channel. The filling and emptying of lock chambers during lock operation leads to oscillations of the free-surface elevation in the channel, which can increase the degree of difficulty encountered in maneuvering a ship and even produce ship accidents in some instances. In previous works, most of the research effort has been devoted to the propagation of long waves in intermediate navigation channels. In contrast, the study of secondary waves in the channels has received less attention so far. In the present study, the development of secondary waves under the layout of decentralized cascade locks for the new waterway in the Three Gorges project was fully considered. A coupled model based on the basic equations of ship locking and Boussinesq equations was first established. Subsequently, the development length of secondary waves and its response to related hydraulic parameters were investigated. The results demonstrated that during lock emptying, the development length of secondary waves was solely related to the maximum discharge per unit width in a form of power function. In contrast, the relationship between the development length and the maximum discharge per unit width was not unique but depended on the initial head of lock chambers during lock filling. Based on the numerical results, two empirical formulas were proposed to predict the development length under different locking operations. The present finding can provide theoretical guidance and technical support for the hydraulic design and operation of decentralized cascade locks.